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1.
Until recently, bioethics (ethics related to biology or, more specifically, in the context of preterm labour, medical ethics) was considered mainly to relate to the active treatment or investigation of patients. Collection of data, excised specimens or even whole organs was considered to be relatively uncontentious as it did not impinge directly upon the health of the individual concerned. However, in the UK in particular, the practice of collecting data, tissues or even whole organs has recently come under the spotlight of public scrutiny, particularly following the Alder Hey Enquiry. Coincidentally with a decline in public confidence in the probity of authority, medical scientists increasingly have to justify the accumulation of data about individuals.  相似文献   
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How many subjects are needed in a longitudinal birth cohort study?   总被引:8,自引:8,他引:0  
One of the first decisions that needs to be taken when planning a birth cohort concerns the size of the study. This in turn will depend on the research questions to be answered and thence whether environmental exposures and outcomes are measured on a continuum or as dichotomous variables. Here we describe ways in which different birth cohorts have addressed this issue and explore the advantages of smaller detailed studies over larger less-detailed studies.  相似文献   
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This study examined the interrater reliability of generalized anxiety disorder (GAD) and major depressive disorder (MDD) diagnoses derived from the Structured Clinical Interview for DSM-III (SCID). Using videotaped interviews, paired raters made independent diagnoses of 75 psychiatric outpatients. The percent agreement of the raters was 82% for MDD and 86% for GAD; the respective kappa values were .72 and .79. The results indicated that the SCID can be employed reliably to differentiate MDD from GAD. The SCID is recommended for further research with these disorders.  相似文献   
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OBJECTIVES: To determine the perinatal outcome of fetuses who had birthweights less than that expected from early third trimester ultrasound scanning. DESIGN: Retrospective estimation of centile fetal weight at early third trimester ultrasound scanning compared with actual centile birthweight corrected for gestational age, parity and sex. SETTING: Teaching Hospital Obstetric Unit, London. SUBJECTS: 197 unselected women with singleton cephalic pregnancies who were delivered at term in our unit between October 1989 and May 1990. MAIN OUTCOME MEASURES: CTG abnormality, need for fetal blood sampling in labour, meconium-staining of the amniotic fluid, mode of delivery, Apgar scores at 1 and 5 min, need for transfer of baby to neonatal unit, and need for neonatal intubation of the neonate at delivery. RESULTS: An actual birthweight greater than 5% less than the birthweight estimated from ultrasound scanning identified 44 babies (22%) with an increased risk of CTG abnormalities (chi 2 = 8.38, P less than 0.0025; Odds ratio (OR) = 2.54; 95% CI 1.36 to 4.78) and need for operative delivery (chi 2 = 5.81, P less than 0.0125; OR = 1.94; 95% CI 1.15 to 3.27), when compared with the remainder of the sample. Overall 14 (32%) of this group had birthweights above the 50th centile. A group of 44 babies selected as being the smallest for gestational age, without reference to growth pattern, had a similar excess morbidity. (All this group had birthweights below the 39th centile). CONCLUSIONS: This study supports the hypothesis that in-utero fetal growth pattern is as important for perinatal outcome as being small for gestational age per se.  相似文献   
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Principal components analyses of the Beck Self-Concept Test (BST) were conducted independently for 288 women with primary mood disorders, 230 women with anxiety disorders, 236 men with mood disorders, and 161 men with anxiety disorders. Four self-concept dimensions that reflected (1) Intellectual Ability; (2) Work Efficacy; (3) Physical Attractiveness; and (4) Virtues/Vices occurred within the four samples. For 5-item subscales that represent these four dimensions, a two-way MANOVA found significant effects for sex and type of disorder. Women described themselves as having less intellectual ability than men did. Outpatients with mood disorders considered their physical appearance, work efficacy, and virtues/vices to be less acceptable than did those with anxiety disorders. Findings were discussed with respect to the cognitive content-specificity theory of psychopathology.  相似文献   
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AIMS: An increase in the proliferative state of the gastric epithelium has been attributed to infection with Helicobacter pylori. In order to obtain a more precise estimate of the magnitude of this change, the proliferative state of 17 cases of florid H pylori associated follicular gastritis was examined using the antibody MIB-1. METHODS: Comparable results were produced from control and gastritis cases by using a combination of two reproducible measures of the labelled cells. Dividing cells in the gastric mucosa are concentrated within a proliferating compartment, situated at the base of the crypts. This compartment was measured and expressed as a proportion of the total crypt length. The proportion of positively labelled cells within the compartment was also counted. RESULTS: The proliferation compartment in the gastritis cases occupied 45.6% of the gastric crypt compared with 15.4% in the control group. Of the cells in the proliferating compartment, 79.5% were positively labelled in the gastritis cases and 33.4% in the control group. CONCLUSIONS: The convoluted nature of the gastric crypt does not make it a forgiving experimental model. The use of long lengths of mucosa obtained from gastrectomy specimens permitted the production of consistent results, using a morphometric method. The greater than 100% difference in the proportion of proliferating cells between the two groups suggests that further investigation is warranted.  相似文献   
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